states.VonMisesFisherDecay
class VonMisesFisherDecay:Predict step for a von Mises-Fisher embedding state.
The mean direction is left unchanged (no appearance motion model); the
concentration decays multiplicatively toward :attr:`kappa_min` with a
time constant :attr:`tau`, so a tracklet that has not been observed
recently becomes less certain of its appearance.
Parameters
| Name | Type | Description |
|---|---|---|
| field | str | Tracklet field holding the mean direction. The concentration lives in ``f"{field}_kappa"``. |
| tau = 10.0 | float | Decay time constant. Each call multiplies ``kappa`` by ``exp(-dt / tau)``. Must be strictly positive. |
| kappa_min = 1.0 | float | Floor on the concentration after decay. |
Raises
- ValueError — If ``tau`` is non-positive.
Members
property
- field
- kappa_fieldReturn the auxiliary concentration field name.
- kappa_min
- tau
Source: unitrack/states/directional.py:52